Firearm receiver



FIG. 1 is a first perspective view of the a firearm receiver showing our new design;

FIG. 2 is a second perspective view thereof;

FIG. 3 is a third perspective view thereof;

FIG. 4 is a fourth perspective view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a left side view thereof;

FIG. 7 is a front end view thereof;

FIG. 8 is a rear end view thereof;

FIG. 9 is a top view thereof; and,

FIG. 10 is a bottom view thereof.

The broken lines illustrate portions of the firearm receiver that form no part of the claimed design. 

CLAIM The ornamental design for a firearm receiver, as shown and described. 